<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>Insert title here</title>
<style type="text/css">

</style>
</head>
<body>
<h1>块内元素</h1>
<div>块1</div>
<div>块2</div>
<div>块3</div>
<h1>行级元素</h1>
<span>行1</span>
<span>行2</span>
<span>行3</span>
</body>
</html>